Keeping in mind there is no such thing as a "Official" pre-apprentice
Under the Laws of Ontario they should not be allowed on job sites..
FYI -
There is such a thing as an "official" pre-apprentice - check out the Government of Ontario web sites. They are pushing pre-apprenticeships in a number of trades.
Under the laws of Ontario a pre-apprentice is certainly allowed on job sites. What WORK they are allowed to do on job sites is another question. It may very well be possible to argue that only an "official" apprentice or journeyman is allowed to perform "electrical" work.
As to the original question posted in this thread: as far as I am aware, there is a ratio only of pre-apprentices to journeymen and a ratio of apprentices to journeymen. There is not necessarily any relationship between the number of apprentices and the number of pre-apprentices employed by any contractor.
It is entirely possible that a contractor could decide to hire NO apprentices and only hire pre-apprentices.
It seems that the policy of the JAC/IBEW Local 353 is that they would rather "organize" hundreds of non-union apprentices than bring in those who would gladly START as union apprentices.
You would likely be better off getting hired by a non-union shop, serving the majority of your time and then getting "organized" than starting out by applying to the JAC to start with.
Good luck.
Regards,
DBT